The present invention relates to copying data in a computer apparatus.
In recent years, HDDs (hard disk drives) used as a storage device in computer apparatus such as personal computers (hereinafter referred to as PCs as occasion demands) have increased in storage capacity.
Users may replace HDDs of their own PCs with such HDDs of larger capacities. In such a case, there is a need to transfer a large amount of data stored in an HDD to be replaced to an HDD having a larger capacity.
Backup of data stored in an HDD is performed comparatively frequently for preparation against occurrence of a fault in the HDD of a PC as well as for transfer of data in the case of replacement of the HDD. In particular, the importance of backup becomes higher with the increase in capacity of HDDs since the loss caused by a fault in an HDD is large if the capacity of the HDD is large. In the case of portable PCs such as notebook PCs, the frequency of occurrence of faults caused by falls is higher than that in the case of desktop PCs. Therefore the importance of backing up data is also very high with respect to such portable PCs.
Conventionally, it is possible to use a backup function provided in an OS (operating system) in the case of transfer of data from an HDD to another HDD or backup of data in an HDD.
This backup function is performed in such a manner that a device is connected to a PC and this device backs up data in a HDD by saving the data to a storage medium such as a tape or a CD-R (CD-recordable).
The backup function provided in the above-mentioned OS requires a high degree of skill by the users, and there is a problem that a user cannot easily and safely back up data in an HDD or transfer the data to another HDD.
Also, a device other than a PC is required for backup. This is also a major reason for the problem that backup is not easy for everyone to perform.
Among recent notebook PCs, a type of notebook PC has appeared which has a portion called a bay or a docking station to which some of various drive units including a CD-ROM or an HDD can be detachably attached. It is conceivable that a backup HDD is attached to such a bay to back up data in a main HDD incorporated in a PC.
However, while backup of data from the main HDD to the backup HDD is being performed, a change is made every moment in the contents of the HDD in a PC in use, i.e., the main HDD, as a change in a file or the like through a LAN for external data communication, an input/output (I/O) device which receives an operating input or the like from a mouse or a keyboard operated by a user or from a CD or a DVD for data read/write, processing in the OS, etc. For this reason, data in the HDD is not fixed (isolated) and the consistency of data cannot be ensured from the point in time at which backup is started to the point in time at which backup is finished. There is, therefore, a possibility of data copied onto the backup HDD becoming unusable as a result of destruction of the file system or the like.
This is because in current PCs during execution of one OS, the PC cannot be changed to execute another OS unless the operation of the first OS is temporarily stopped by a restart of the PC or the like.
Even if backup can be reliably performed, there is also a problem that, for example, in a case where a fault occurs in an HDD of a PC and where data in the HDD is restored by using a backup of the data, reinstallation of the OS in the HDD of the PC, reinstallation of various device drivers, copying of the backup data, etc., are necessary, certain skills are required for them, and such operations are considerably troublesome and time-consuming.
Some of recent PCs have a so-called recovery function, i.e., the function of instantly restoring data in an HDD to the state at the time of shipment of the PC from a maker (hereinafter referred to as “initial state”) when a fault or the like occurs.
Such a recovery function can be realized in such a manner that a predetermined key is operated during POST (Power on Self Test) automatically executed at the time of startup of a PC to make a recovery program run without starting an ordinary OS (Windows(Trademark of the Microsoft Corporation (Redmond, Wash.), for example).
By this operation, however, data in the HDD is replaced with that in the initial state of the HDD at the time of shipment from a factory and all of applications, data, etc., installed by a user after purchase of the PC are thereby lost.
The present invention has been achieved by considering technical problems such as those described above, and a main purpose of the present invention is to provide a technique for enabling a dead copy of data to be made safely and reliably. As here used, the phrase “dead copy” refers to a copy which is fixed and unchanging, as distinguished from a “live copy” in which changes are ongoing.
Another purpose of the present invention is to provide a technique for enabling an OS in operation to be changed to another OS.